Roman Nights by Dorothy Dunnett

tried to think of a way of not telling Jacko what he was asking. The trouble with Jacko is that he really does go for Di. I said, ‘You’ll never guess who we saw in the Barberini. The man who sold Charles and me the balloon outside the zoo. We ran after him and lost him somewhere in the Corso.’
    ‘At the Fall Fair?’ said Jacko, arrested. ‘You’re dreaming. The Yanks wouldn’t let a street trader in – not if he went through a car wash and wax spray with Dettol. Ruth, precious, you’ve seen too many teleromanzos on the goggle box.’
    I said, ‘He was specially scoured for the occasion. Johnson’s got a photograph. I couldn’t stop him. There is shortly going to be a sonic boom at the Trust which could be felt in three continents, and I only hope I’m not there to hear it. In the meantime, that unfortunate star is going to set in forty minutes.’
    ‘I’m off.’ Jacko said. The cool air flowed in from the cupola. Warm from bed, I felt it on my face, but not at all through my thick jersey and anorak. In the dim light Jacko’s face looked like a clown’s, with sad eyes and tangled hair and Zapata moustache. I said, ‘I’m going back after five to have breakfast. You can bunk downstairs here, if you want to.’
    ‘Thanks,’ said Jacko morosely.
    ‘Without service and back-up facilities,’ I called after him, and heard him make a rude noise as I shut the door and swung up the bench and prepared the filter and plate for their holder. I heard his footsteps ring down the spiral stair, and then clack on the marble one lower. An inner door shut. He was going to stay.
    It had happened before. We didn’t bother each other. Work was work, and like Charles he occupied himself as a rule in the developing room, or reading, or listening to the British Forces Network or the Voice of America and making endless cups of coffee before turning in. I would be brought a mug and a sandwich, or perhaps join him in one halfway between exposures. But most times the place would be dark if I went downstairs, and Charles, or Jacko, asleep. Innes, who had been known to work all night on his Incubator, never came into the Dome in the evening.
    But tonight Charles was asleep in my digs and Innes, it seemed, tucked up in his, stoned to the eyeballs. For slights received, Timothy had taken vengeance.
    The telescope reared black above me, its cold metal bulk like a cannon, with the finder and guider tubes ranged alongside like gun barrels. The stepladder glinted in the starlight, and behind it stood the skeleton of the quarter-ton crane. Once a year, through the trapdoor below me, the mirror would descend for its aluminium coating. Mirrors are heavy, to avoid warping. I have known them to weigh almost a ton.
    I switched on the power for the rings and the green slot light which showed the declination numbers and pointer. The 50-Inch was an old one, with Roman numbers. I like Roman numbers. I set and clamped it.
    The right advancement is more difficult: you have to subtract the number twice from the sidereal clock before setting. I did it, and fine-set it and then undamped the main movement and pressed the switch which starts the telescope moving.
    However quick you are, you must always be accurate. The filter must be put in right side up, with the surface matt and not shiny. You must remember to uncap all three of your telescopes. You must remember to take the time as you slide in the plateholder, and to open the shutter at the end of the 50-Inch. Then you must watch, all through the exposure, that the telescope follows the arc of its subject, with the slow-motion button held in your hand.
    You learn as a student how to relax, how to look steadily with one eye and not to screw up and weary the other. At first, you are allowed to cover the idle eye with your hand. Then the knack comes to you and you can stare with one eye into the lens of a telescope while the other looks into darkness, seeing nothing. I have known Charles to move